On Definition: A Lecture in Logic

Submitted by admin on Mon, 05/30/2011 - 04:24

On Definition: A Lecture in Logic

DEFINITION IS A STATEMENT that gives the meaning of a term or explains what a term means. As it clarifies the limits by which a word or term should be used and understood, definition helps eliminate confusion and ambiguity in the use of terms, thereby minimizing, if not totally eradicating, misunderstanding and misconception in communication.

Definition comprises two elements: the definiendum or the term to be defined; and the definiens or the defining term. In the definition, “Mathematics is the study of the relationships among numbers, shapes, and quantities,” Mathematics is the definiendum and the study of the relationships among numbers, shapes, and quantities is the definiens.

4 Main Types of Definition

1. Nominal definition or ‘definition by name’ simply conveys what the term means, not what the thing is.

Kinds of Nominal Definition

a. Etymological definition gives the root word, derivation, or origin of a term.

Examples:

Philosophy (philia, love; Sophia, wisdom) is love of wisdom.

Agoraphobia (“agora”, open space; “phobia”, fear) is the fear of open or public spaces.

Transport (“trans”, across; “portare”, to carry) means, “to carry across”.

Pantheism (“pan”, all; “theos”, God; “ismos”, system of belief) is thebelief that God is everything and everything is God.

b. Synonymous definition gives theequivalent word (which is usually the better known or more common) of the term being defined.

Example:

Novice means “beginner.”

Aficionado means “enthusiast”.

Crimson means “red”.

c. Biverbal definition gives the translation of the term in another language.

Example:

Vox populi means “voice of the people”.

Caveat means “warning or proviso”.

A bundok is a “mountain”.

d. Definition by full form gives the word or group of words represented by abbreviation (shortenings, contractions, initialisms, and acronyms.)

Examples: Shortenings cont. means continued; km. means kilometer; hippo means hippopotamus; limo means limousine; bus means omnibus; taxi means taxicab; deli means delicatessen; zoo means zoological garden; bike means bicycle.

Examples: Contractions

Dr.means doctor, St. means saint or street; couldn’t means could not; didn’t means did not, we’ve means we have.

Examples: Initialisms

CSI is Crime Scene Investigation; LA is Los Angeles; A.W.O.L. is absent without official leave; a.m. is ante meridiem

Examples: Acronyms

AIDS is Acquired Immune Deficiency Syndrome; laserislight amplification by stimulated emission of radiation; scuba is self-contained underwater breathing apparatus; UNESCO is United Nations Educational, Scientific, and Cultural Organization.

2. Denotative definition or definition by example elucidates the meaning of a term by mentioning or showing its referent/s.

Kinds of Denotative Definition

a. Demonstrative definition or ostensive definition explicates the meaning of a term by showing or pointing at the object.

For instance, a teacher may explain the meaning of a “laptop” by bringing one and showing it to the class. A boxing trainer may try to answer the question, “What does ‘left hook’ mean?” by executing it. Proper names, like “Pres. Obama” may also be defined ostensively.

b. Enumerative definition is done by naming the referents of the term.

Ex: If someone asks, “What is a fruit?” and we answer by saying, “The apple is a fruit. The orange is a fruit. The mango is a fruit. The guava is a fruit.”

3. Descriptive definition elucidates the meaning of a term by citing the essential or accidental characteristics of the referent/s of the term.

Kinds of Descriptive definition

a. Distinctive definition mentions the property of a thing that emanates from its essence or unique trait.

Ex: Man can have sense of humor. (Ability to see something as funny is a property of man, which arises from his being rational).

H20 can take the solid, liquid, and gas state of matter.

b. Accidental definition explains a thing by stating its contingent or unessential characteristics.

Examples:

The house has three bathrooms.

The car is yellow.

Kobe Bryant has tattoos.

c. Genetic definition explains how a thing originated or depicts how something is produced.

Example:

Yeast breads are made by mixing, kneading, and rising the dough, then shaping and baking the bread.

Pepsi-Cola (Pepsi) is a mixture of carbonated water, cane-sugar syrup, and an extract from tropical kola nuts.

A lunar eclipse occurs when the earth is between the sun and the moon and its shadow darkens the moon.

A solar eclipse happens when the moon is between the sun and the earth and its shadow moves across the face of the earth.

d. Definition by efficient cause gives the maker or producer of a thing.

Examples:

Nike, Inc. was founded by former track athlete Philip Knight and his college coach William Bowerman.

The Chronicles of Narnia was written by C. S. Lewis.

Candies are made by a confectioner.

The Bible was written by God’s selected servants through His commissioning and inspiration.

e. Definition by final cause declares the purpose or end of which a thing is produced.

Examples:

School is an institution for teaching students.

Exercise is an activity undertaken to enhance general physical health.

A calculator is a device used to compute arithmetic operations.

4. Connotative definition or essential definition provides the nature or essential characteristics of the referents denoted by a term. It has two elements: the genus or the property that a thing has in common with its co-members in the same class, and the specific difference orthe thing’s essential property that distinguishes it from other members of the same class.

Examples:

Octagon is a polygon with eight sides.

Dictionary is a reference book of word meanings or equivalents.

Tsunami is a large ocean wave caused by an underwater earthquake or another movement of the Earth's surface.

Blizzard is a storm characterized by extreme cold, strong winds, and a heavy snowfall.

Rules of a Good Connotative Definition

Connotative definition is very much useful in logic because it is a definition, which alone gives the essential meaning of a term. It helps eliminate ambiguity and it reduces the vagueness of the term in its essential attributes. The following are some rules in making a connotative definition:

1. The defining term must be equivalent to the term being defined. The definition must neither be too broad nor too narrow.

The definition,A typhoon is a violent storm is too broad since hurricane and blizzard, which are different from typhoon, are also violent storms. A guitar is a stringed musical instrument is also too broad definition because many musical instruments other than guitar are also stringed.

On the other hand, the definition Martial Arts are Korean Tae Kwon Do is too narrow as it excludes Aikido, Judo, Karate, and other forms of martial arts. Same is the case of A basketball player is a point guard for it excludes basketball players who are playing other positions.

2. Definition should not be circular. The term being defined should not be contained in the defining term; otherwise, the definition gives little or no information at all and thus fails in its purpose to explain the meaning of a term.

Examples:

A player is one who plays.(Circularity can be avoided by saying A player is somebody taking part in a sport game.)

A cookbook is a book for cooking. (Better: A cookbook is a book containing recipes and directions for preparing food.)

An answering machine is a machine that answers. (An answering machine is a phone recording device that plays a message to callers and records messages from them.)

A green card is a card that is green. (In the United States, a green card is an identity card and work permit issued to nationals of other countries.)

A blue book is a book that is blue. (It is a blank notebook used in schools for writing examination answers.)

3. The definition must be stated in univocal and simple terms. The definition should not be expressed in obscure, ambiguous, or figurative language. In defining terms, perplexing and highly theoretical explanations, as well as subjective judgments, must be avoided.

Examples:

Figurative definitions:

Marriage is a bribe to make the housekeeper think she's a householder.--Thornton Wilder (1897 - 1975)

Science is a first-rate piece of furniture for a man's upper chamber, if he has common sense on the ground floor.--Oliver Wendell Holmes (1809 - 1894)

Dreams are cages within which we observe the cages without.--William Wantling (1933 - 1974)

Beauty is a shell from the sea where she rules triumphant till love has had its way with her.--William Carlos Williams (1883 - 1963)

Friendship is a disinterested commerce between equals; love, an abject intercourse between tyrants and slaves. – Oliver Goldsmith (1730 - 1774)

Obscure definitions:

Life is our reaction to the basic insecurity which constitutes its substance.--José Ortega y Gasset (1883 - 1955)

Reason is…a wonderful and unintelligible instinct in our souls, which carries us along a certain train of ideas, and endows them with particular qualities, according to their particular situations and relations.--David Hume (1711 - 1776)

Consciousness… is of a teeming multiplicity of objects and relations, and what we call simple sensations are results of discriminative attention, pushed often to a very high degree.--William James (1842 - 1910)

Consciousness is thoroughgoing dialectical restlessness, this melee of presentations derived from sense and thought, whose differences collapse into oneness.--G. W. F. Hegel (1770 - 1831)

Reason is…an act of faith to assert that our thoughts have any relation to reality at all.--G. K. Chesterton (1874 - 1936)

Subjective definitions:

Death is my neighbour now.--Edith Evans (1888 - 1976) (British actor.

Said a week before her death)

Happiness [is] a good bank account, a good cook, a good digestion.--attributed to Jean-Jacques Rousseau (1712 - 1778)

Philosophy [is] living voluntarily among ice and high mountains—seeking out everything strange and questionable in existence, everything so far placed under a ban by morality. -- Friedrich Wilhelm Nietzsche (1844 - 1900)

Love is the difficult realization that something other than oneself is real.--Iris Murdoch (1919 - 1999)

Opera is when a guy gets stabbed in the back and instead of bleeding he sings.

--Ed Gardner (1904 - 1963)

4. The definition should not be needlessly negative. As much as possible, the definition must be in the affirmative form for it must explain what a term means rather than what it does not.

To define basketball as “a ballgame that is neither volleyball nor football” is obviously to fail to explain its meaning. Notice too that there are many other kinds of ballgame, aside from volleyball and football, which are not meant by the term basketball.

Other examples:

A male is not a female.

Long is the opposite of short.

A ball pen is neither a pencil nor a chalk.

Moral is that which is not immoral.

Negative definition, nonetheless, are accepted for terms whose meaning are necessarily negative (e.g. Infinity is a state of being which is without limits) and when the terms refer to a privation (e.g. A deaf is someone who cannot hear.)